Page "Asteroids (video game)" Paragraph 5

Each stage starts with a few asteroids drifting in random directions on the screen.

Objects wrap around screen edges – for instance, an asteroid that drifts off the top edge of the screen reappears at the bottom and continues moving in the same direction.

As the player shoots asteroids, they break into smaller asteroids that frequently move faster and are more difficult to hit.

Smaller asteroids also score higher points.

Periodically, a flying saucer appears on one side of the screen and moves across to the other before disappearing again.

The saucers are of two kinds: Large saucers fire in random directions, while small saucers aim at the player's ship.